THE GERMINATION PATTERN OF A NATIVE DANDELION (TARAXACUM PLATYCARPUM) AS COMPARED WITH INTRODUCED DANDELIONS

Abstract

This study focuses on the germination of dandelions as the first step in their life cycle and shows the characteristics of the germination pattern in some dandelion species through a field survey and germination experiments. The introduced dandelions T.laerigatum and T.officinale have a synchronous nature in germination. On the other hand, seed populations of T.platycarpum are heterogenous in germination behaviour, and the seed germination in this dandelion is suppressed by the high summer temperature in Tokyo. The germination period in this dandelion is, therefore, divided into two seasons, carly summer and autumn. This two-season germination pattern is discussed from the viewpoint of adaptive strategies for the establishment of this dandelion species.